Astronomer Ken Croswell, author of Magnificent Mars and Magnificent Universe, discusses the Hubble Space Telescope. Also, the Environmental Protection Agency says 1 in 5 counties in the U.S. are in violation of air standards; Study says only 12% of endangered species analyzed live in protected areas; Worlds oldest mouse found; Hubble photographs farthest planetoid from the Sun, raising questions about the nature of the solar system; FDA approves device that links the brain directly to a computer.